1. Field of Invention
The present invention relates to a power device package and a method of fabricating the same, and more particularly, to a power device package, which can be made compact by vertically stacking substrates on which semiconductor chips are mounted, and a method of fabricating the power device package.
2. Description of the Related Art
As the power electronic industry continues to use power devices (e.g., a power transistor, an insulated-gate bipolar transistor (IGBT), a MOS transistor, a silicon-controlled rectifier (SCR), a power rectifier, a servo driver, a power regulator, an inverter, or a converter), demands for lighter and smaller power products having better performance are increasing.
To meet the demands, smart power modules or intelligent power modules which can integrate not only various power semiconductor chips but also control semiconductor chips, such as integrated circuit chips, for controlling the power semiconductor chips, into one package, have been actively studied.
FIG. 1A is a top plan view of a conventional power device package 1. FIG. 1B is a cross-sectional view taken along line A-A of FIG. 1A.
Referring to FIGS. 1A and 1B, the conventional power device package 1 includes a first substrate 2 and a second substrate 3 which are disposed horizontally. In general, power semiconductor chips 6 are mounted on the first substrate 2, and control semiconductor chips 7 are mounted on the second substrate 3. The first substrate 2 and the second substrate 3 are electrically connected to each other by using a wire 8. Each of the first substrate 2 and the second substrate 3 is electrically connected to a lead frame 4, and is electrically connected to the outside of the conventional power device package 1 through external leads 5. A sealing member 9 seals the power semiconductor chips 6 and the control semiconductor chips 4, thereby completing the conventional power device package 1. U.S. Pat. No. 5,703,399 assigned to Mitsubishi discloses such a conventional power device package in which power semiconductor chips and control semiconductor chips mounted on one lead frame are molded into one package.
However, since the power semiconductor chips and the control semiconductor chips are horizontally mounted on the lead frame facing a substrate, it is difficult to reduce the area of the conventional power device package. Therefore, there is a limitation in increasing the integration density of the conventional power device package.